Herbal antitussives

Efficacy and tolerability of SEDIFLÙ in treating dry or productive cough in the pediatric population (SEPEDIA): A pilot, randomized, double-blind, placebo-controlled, multicenter clinical trial

The aim of this trial was to assess the effectiveness of Sediflù, a medical device containing active herbal ingredients, on nocturnal and diurnal persistent coughs in children, with a duration of 3 to 7 days. Children with a dry and/or productive cough were enrolled in this prospective, interventional, multicenter, placebo-controlled, double-blind, randomized clinical study. Clinical efficacy was assessed through the evaluation of the soothing action of Sediflù against dry and/or productive coughing, both at night and during the day, and other effects of coughing associated with quality of sleep: frequency, child's quality of sleep, parental quality of sleep and severity. Treatment with Sediflù improved both night-time and day-time cough scores from day 2. The diurnal score also improved significantly in the Sediflù group at days 3 and 7. Sediflù syrup can be considered a valid treatment for cough management in younger children with upper respiratory tract infections, shortening the cough duration.

Modulation of transient receptor potential (TRP) channels by plant derived substances used in over-the-counter cough and cold remedies

BACKGROUND

Upper respiratory tract infections (URTIs) impact all age groups and have a significant economic and social burden on society, worldwide. Most URTIs are mild and self-limiting, but due to the wide range of possible causative agents, including Rhinovirus (hRV), Adenovirus, Respiratory Syncytial Virus (RSV), Coronavirus and Influenza, there is no single and effective treatment. Over-the-counter (OTC) remedies, including traditional medicines and those containing plant derived substances, help to alleviate symptoms including inflammation, pain, fever and cough.

PURPOSE

This systematic review focuses on the role of the major plant derived substances in several OTC remedies used to treat cold symptoms, with a particular focus on the transient receptor potential (TRP) channels involved in pain and cough.

METHODS

Literature searches were done using Pubmed and Web of Science, with no date limitations, using the principles of the PRISMA statement. The search terms used were 'TRP channel AND plant compound', 'cough AND plant compound', 'cough AND TRP channels AND plant compound', 'cough AND P2X3 AND plant compound' and 'P2X3 AND plant compound' where plant compound represents menthol or camphor or eucalyptus or turpentine or thymol.

RESULTS

The literature reviewed showed that menthol activates TRPM8 and may inhibit respiratory reflexes reducing irritation and cough. Menthol has a bimodal action on TRPA1, but inhibition may have an analgesic effect. Eucalyptus also activates TRPM8 and inhibits TRPA1 whilst down regulating P2X3, aiding in the reduction of cough, pain and airway irritation. Camphor inhibits TRPA1 and the activation of TRPM8 may add to the effects of menthol. Activation of TRPV1 by camphor, may also have an analgesic effect.

CONCLUSIONS

The literature suggests that these plant derived substances have multifaceted actions and can interact with the TRP 'cough' receptors. The plant derived substances used in cough and cold medicines have the potential to target multiple symptoms experienced during a cold.

Efficacy and safety of the syrup "KalobaTUSS®" as a treatment for cough in children: a randomized, double blind, placebo-controlled clinical trial

BACKGROUND

Acute cough in children often causes discomfort to children and parents, reducing their quality of life. Despite the extensive utilization of over-the-counter remedies for cough, the efficacy of most of these treatments in children has not been confirmed.

METHODS

We conducted a randomized, double blind, placebo-controlled clinical trial of 106 children with acute cough to evaluate the efficacy and safety of KalobaTUSS®, a paediatric cough syrup based on acacia honey and on Malva sylvestris extract, Inula helenium extract, Plantago major extract, and Helichrysum stoechas extract by using a validated 6 points Likert scale.

RESULTS

Children were orally treated with KalobaTUSS® or placebo for 8 days. Children receiving KalobaTUSS® showed an early and significant reduction in night-time and day-time cough scores measured using a specific scale and a shorter duration of cough than children treated with the placebo.

CONCLUSIONS

KalobaTUSS® is well tolerated and produces positive effects by reducing the severity and shortening the duration of cough in children.

TRIAL REGISTRATION

Clinicaltrials.gov no. NCT04073251 . Retrospectively registered.

Stability Study and a 14-Day Oral Dose Toxicity in Rats of Plantain Leaf Extract (Plantago lanceolata L.) Syrup

Plants have been used since antiquity to treat and prevent diseases. Plantain (Plantago lanceolata L.) is traditionally used for the treatment of the common cold and associated symptoms such as cough. This study was designed to evaluate the oral toxicity of plantain leaf extract-containing syrup. In preparation of the toxicological examination and to ensure the quality of the herbal preparation, analytical methods were developed and validated, and stability testing was performed. Physicochemical and microbial quality, thin layer chromatography patterns and high performance liquid chromatography fingerprints complied with the specifications during the entire period of stability testing. The marker substance, acteoside, remained within the stability-defining limits of 90%-110% for quantitative determinations. No hint of toxicity emerged from 14-day repeat dose toxicity testing in rats. The animals were given doses of 3, 6, or 12 mL of syrup per kg body weight by gavage twice daily. All animals showed normal appearance and behavior. Body and organ weights at the end of the study were similar to those in the control group. Overall, P. lanceolata syrup was found to be stable and non-toxic under the test conditions.

Herbal Medicine for Cough: a Systematic Review and Meta-Analysis

BACKGROUND

The aim of this review was to systematically assess the literature on herbal medicine for cough as a symptom of upper respiratory tract infections and common cold.

METHODS

The Cochrane Library, Scopus, MEDLINE/PubMed, and Embase were searched through March 2012 for RCTs testing the effects of herbal medicine for cough. Risk of bias was assessed using the Cochrane tool.

RESULTS

34 RCTs (N = 7,083) on Pelargonium sidoides (11 RCTs), Echinacea (8 RCTs), Andrographis paniculata (6 RCTs), ivy/primrose/thyme (4 RCTs), essential oils (4 RCTs) and bakumondoto (1 RCT) were included. Controls were mainly placebo. Most studies had a low risk of bias. The meta-analysis revealed strong evidence for A. paniculata (SMD = -1.00, 95% CI = -1.85, -0.15; P<0.001) and ivy/primrose/thyme (RR = 1.40, 95% CI = 1.23, 1.60; P<0.001) in treating cough; moderate evidence for P. sidiodes (RR = 4.60; 95% CI = 2.89,7.31; P<0.001), and limited evidence for Echinacea (SMD = -0.68; 95% CI = -1.32, -0.04; P = 0.04).

CONCLUSION

This review found strong evidence for A. paniculata and ivy/primrose/thyme-based preparations and moderate evidence for P. sidoides being significantly superior to placebo in alleviating the frequency and severity of patients' cough symptoms. Additional research, including other herbal treatments, is needed in this area.

Antimicrobial Activity of Cladonia verticillaris Lichen Preparations on Bacteria and Fungi of Medical Importance

Cladonia verticillaris lichen lectin (ClaveLL) was purified using a previously established protocol and then evaluated for its potential antimicrobial activity. Initially, the autochthonous lichen was submitted to extraction with sodium phosphate buffer pH 7.0, followed by filtration and centrifugation to obtain crude extract. A salt fractionation was performed with 30% ammonium sulfate. After centrifugation, the protein fraction was loaded onto molecular exclusion chromatography using Sephadex G-100 matrix to purify active lectin. ClaveLL showed antibacterial activity against Gram-positive (Bacillus subtilis, Staphylococcus aureus, and Enterococcus faecalis) and Gram-negative (Escherichia coli and Klebsiella pneumoniae) assayed strains, with greater inhibitory effect on growth of E. coli (MIC of 7.18 μg mL−1). The lowest minimum bactericidal concentration (MBC, 57.4 μg mL−1) was detected against E. faecalis. The antifungal assay performed with Trichophyton mentagrophytes, Microsporum gypseum, Trichophyton rubrum, Trichosporon cutaneum, and Trichosporon asahi evaluated crude extract, fraction, and ClaveLL preparations. ClaveLL was the most active against T. rubrum with an inhibition percentage of 35% compared to negative control (phosphate buffer). Extract and fraction showed better activity on growth inhibition of T. mentagrophytes (35%). The results indicate the potential of ClaveLL and other C. verticillaris preparations as antimicrobial agents useful for applications focusing on human health.

Antitussive Efficacy and Safety Profile of Ethyl Acetate Fraction of Terminalia chebula

Antitussive effects of ethyl acetate fraction of Terminalia chebula on sulphur dioxide (SO₂) gas induced cough have been examined in mice. Safety profile of Terminalia chebula was established by determining LD₅₀ and acute neurotoxicity. The result showed that extract of Terminalia chebula dose dependently suppressed SO₂ gas induced cough in mice. Terminalia chebula, after i.p. administration at dose level 500 mg/kg, offered maximum cough suppressive effects; that is, number of coughs at 60 min was 12 ± 1.52 (mean ± SEM) as compared to codeine 10 mg/kg; i.p., dextromethorphan 10 mg/kg; i.p., and saline, having frequency of cough 10.375 ± 0.866, 12.428 ± 0.81, and 46 ± 2.61, respectively. LD₅₀ value of Terminalia chebula was approximately 1265 mg/kg, respectively. No sign of neural impairment was observed at antitussive doses of extract. Antitussive effect of Terminalia chebula was partly reversed with treatment by naloxone (3 mg/kg; s.c.) while rimcazole (3 mg/kg; s.c.) did not antagonize its cough suppression activity. This may suggest that opioid receptors partially contribute in antitussive action of Terminalia chebula. Along with this, the possibility of presence of single or multiple mechanisms activated by several different pharmacological actions (mainly anti-inflammatory, antioxidant, spasmolytic, antibacterial, and antiphlegmatic) could not be eliminated.

Expectorant and antioxidant activities of purified fumarprotocetraric acid from Cladonia verticillaris lichen in mice

The lichen Cladonia verticillaris produces bioactive secondary metabolites, such as fumarprotocetraric (FUM) and protocetraric acids. Species of the genus Cladonia demonstrate anti-tumor, anti-inflammatory and antipyretic activities and have been used in folk medicine to treat respiratory diseases (throat irritation, cough, asthma and tuberculosis). The aim of the present study was to evaluate the expectorant and mucolytic activities of fumarprotocetraric acid in albino Swiss mice. FUM was extracted and purified from an acetone extract of C. verticillaris. The phenol red quantification method was used on the bronchoalveolar lavage fluid following the administration of FUM (25, 50 or 100 mg/kg orally or intraduodenally and 12.5, 25 or 50 mg/kg, intraperitoneally) for the evaluation of expectorant activity. Control groups received either saline solution (7.5 mL/kg) or ambroxol (1 mg/kg) through the same administration routes. Antioxidant activity was evaluated using the thiobarbituric acid reactive species assay in mouse lung tissue treated with the FUM at 25, 50 or 100 mg/kg orally, followed by a lipopolysaccharide solution at 1 mg/kg intrapleurally. The same protocol was used for the control groups using either saline solution (7.5 mL/kg, orally) or N-acetylcysteine (20 mg/kg, orally).

RESULTS

Orally administered FUM at doses of 25 and 50 mg/kg promoted significantly greater dose-dependent phenol red activity in the bronchoalveolar lavage and expectorant activity in comparison to the controls (p < 0.05). Lipid peroxidation (malondialdehyde equivalent) was reduced by 50% in the lung tissue.

CONCLUSION

The results confirm the expectorant and antioxidant properties of fumarprotocetraric acid produced by the lichen C. verticillaris.

Effect of honey on nocturnal cough and sleep quality: a double-blind, randomized, placebo-controlled study

OBJECTIVES

To compare the effects of a single nocturnal dose of 3 honey products (eucalyptus honey, citrus honey, or labiatae honey) to placebo (silan date extract) on nocturnal cough and difficulty sleeping associated with childhood upper respiratory tract infections (URIs).

METHODS

A survey was administered to parents on 2 consecutive days, first on the day of presentation, when no medication had been given the previous evening, and the following day, when the study preparation was given before bedtime, based on a double-blind randomization plan. Participants included 300 children aged 1 to 5 years with URIs, nocturnal cough, and illness duration of ≤ 7 days from 6 general pediatric community clinics. Eligible children received a single dose of 10 g of eucalyptus honey, citrus honey, labiatae honey, or placebo administered 30 minutes before bedtime. Main outcome measures were cough frequency, cough severity, bothersome nature of cough, and child and parent sleep quality.

RESULTS

In all 3 honey products and the placebo group, there was a significant improvement from the night before treatment to the night of treatment. However, the improvement was greater in the honey groups for all the

CONCLUSIONS

Parents rated the honey products higher than the silan date extract for symptomatic relief of their children's nocturnal cough and sleep difficulty due to URI. Honey may be a preferable treatment for cough and sleep difficulty associated with childhood URI.

Investigation of antitussive and toxicological activity of Ballota limbata in mice

CONTEXT

Ballota limbata Benth. (Lamiaceae) (syn, Otostegia limbata Hook.f.) is a species grown in the North West Frontier Province and the lower hills of West Punjab, Pakistan. Ballota species are renowned for their antispasmodic, antiulcer, diuretic, vermifuge, and especially sedative effects. However, little is known about the biological activity of B. limbata.

OBJECTIVE

Evaluation of antitussive activity and safety profile of dried B. limbata extract.

MATERIALS AND METHODS

Whole air-dried plants were partitioned with various solvents and the butanol fraction was subjected to antitussive evaluation using a sulfur dioxide (SO(2))-induced cough model in mice. Codeine and dextromethorphan were used as positive control. Safety profile of the testing material was established using standard toxicity tests.

RESULTS

B. limbata extract inhibited cough provoked by SO(2) gas in mice in a dose-dependent manner. The extract exhibited maximum protection against SO(2)-induced cough after 60 min of administration. B. limbata offered maximum cough suppressive effects, that is, number of coughs during 60 min was 11.66 ± 1.2 (mean ± SEM), after s.c. administration of 800 mg/kg, as compared with codeine 10 mg/kg, s.c., dextromethorphan 10 mg/kg, s.c., and saline showing a frequency of cough of 11.75 ± 1.18, 12.25 ± 0.83, and 46.25 ± 1.52, respectively. LD(50) value of B. limbata was greater than 5000 mg/kg. No sign of neural impairment was observed at antitussive doses and the extract has been well-tolerated at higher doses.

DISCUSSION AND CONCLUSION

This study demonstrates that the extract of B. limbata has shown strong cough suppressive effect in mice without yielding any notable toxicity.

In vivo anti-tussive activity and structural features of a polysaccharide fraction from water extracted Withania somnifera

AIM OF THE STUDY

Anti-tussive drugs are amongst the most widely used medications worldwide; however no new class of drugs has been introduced into the market for many years. The present study aims at evaluating the structural features and in vivo anti-tussive activity of a polysaccharide fraction from water extracted Withania somnifera.

MATERIALS AND METHODS

Herein, we have analyzed water extracted material of Withania somnifera using chemical, chromatographic, spectroscopic and biological methods.

RESULTS

A polysaccharide fraction (F3) containing arabinosyl, galactosyl and galacturonosyl residues were obtained by anion exchange chromatography of the water extracted material. This polymer is branched and contained (1,5)-/(1,3,5)-linked arabinofuranosyl, (1,3)-/(1,6)-/(1,3,6)-linked galactopyranosyl residues together with small amount of terminal rhamnopyranosyl and terminal arabinofuranosyl residues. Peroral administration of this pectic arabinogalactan in a dose of 50 mg kg(-1) body weight (b.w.) decreased the number of cough efforts induced by citric acid in guinea pigs like that of codeine.

CONCLUSIONS

This study provides a scientific basis for the past and present ethnomedical uses of this plant.

Clinical cough V: complementary and alternative medicine: therapy of cough

We review the actions of complementary and alternative medicines (CAMs) in the treatment of cough and of the conditions associated with it; in particular asthma and upper respiratory tract infections. These therapies may work (1) peripherally, at the sites in the airways and lungs at which cough is being activated, (2) in the brainstem, where the neural "cough center" is situated, or (3) at the cerebral cortex, where cough can be initiated, suppressed or modified by conscious or unconscious controls. Of the large number of trials of CAMs against cough, most are inadequate in design. It may be difficult to randomize selection. Blinding is often impossible both for the patient and the therapist, and adequate placebo controls may be difficult to devise. The patient can usually identify the "active" treatment by the taste or smell of a medicine, or from the approach and apparatus being used. Pure chemicals can be extracted from many of the herbs used as antitussives, and can be shown to be effective in randomized, blind, and controlled trials, but it does not follow that the herb itself, used in the recommended formula and shown to be antitussive, acts by this agency unless a placebo effect is ruled out. A few herbs are identified where the evidence points to a true antitussive action. Of nonherbal treatments, the few positive results are usually outweighed by the larger number of negative ones. Thus, in general, CAMs for cough are welcomed enthusiastically by the patient but lack sound evidence for their efficacy. Antitussive chemicals can be extracted from many herbs, but it is no more than a reasonable hypothesis that the herb itself acts through this pathway.

Sesame oil use in ameliorating cough in children: A randomised controlled trial

OBJECTIVES

To examine the role of sesame oil (SO) in reducing the frequency and severity of acute cough in children 2-12 years of age.

DESIGN

Double blind, placebo controlled randomised trial.

SETTING

Seven primary health care centres/clinics in Lebanon. A total of 107 children between the age of 2 and 12 years with cough secondary to common cold were enrolled.

INTERVENTION

Five milliliters of SO or placebo by mouth at bed time.

OUTCOME MEASURES

Cough strength and frequency as judged by parents on a four points Likert scale after giving three syrup doses over three consecutive nights. Analysis was performed on an intention to treat basis.

RESULTS

At day 1, the effect size for cough frequency and cough strength were +0.26 (95%CI -0.64,+0.12) and +0.15 (95%CI -0.53, +0.23), respectively. SO decreased cough symptoms more than placebo but these were not statistically significant. The effect size decreased from days 1 to 3. Cough symptoms improved over the 3 days both in SO and placebo group. No evidence of undesirable effects were noted to SO.

CONCLUSION

Like other over the counter antitussives, SO did not result in marked improvement in cough symptoms.